News tagged with hydrogen bonds

Many phenomena depend on the connectivity of hydrogen bonds. Scientists have strived to unlock mysteries about how the network of hydrogen bonds in water controls its behavior since 1806 when Theodor Grotthuss published his ...

(Phys.org)—What happens at the molecular level when salt dissolves in water? In introductory chemistry classes, we learn about the solubility of salts that dissociate into ions in water. Water has a complex hydrogen bonding ...

(Phys.org)—A trio of researchers with Princeton University has found a way to weaken the strong bonds between the nitrogen and hydrogen atoms in ammonia molecules while simultaneously releasing a single hydrogen atom to ...

There are two types of liquid water, according to research carried out by an international scientific collaboration. This new peculiarity adds to the growing list of strange phenomena in what we imagine is a simple substance. ...

(Phys.org)—A team of researchers from several institutions in Spain and France has conducted the first quantitative study of liquid water combining dielectric relaxation and neutron scattering, and in so doing, has revealed ...

Hydrogen (H2) is an extremely simple molecule and yet a valuable raw material which as a result of the development of sophisticated catalysts is becoming more and more important. In industry and commerce, applications range ...

The rise of 3-D printing means it's now easy to create objects to any design we like from scratch, something that's already finding particular use in medicine, with 3-D printed customised prosthetics or even replacement bones ...

Scientists from MIPT and several research teams working in Russia and other European countries have been the first to reliably realize and document the phenomenon of water molecular dipoles ordering by confining water molecules ...

DNA, our genetic material, normally has the structure of a twisted rope ladder. Experts call this structure a double helix. Among other things, it is stabilized by stacking forces between base pairs. Scientists at the Technical ...

Opening a broad vista in the search for effective pharmaceuticals, a collaboration of Chinese and U.S. chemists has laid out a highly efficient new method to convert abundant organic molecules into new medicines.

Hydrogen bond

A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, like nitrogen, oxygen or fluorine (thus the name "hydrogen bond", which must not be confused with a covalent bond to hydrogen). The hydrogen is covalently bonded to another electronegative atom. The energy of a hydrogen bond (typically 5 to 30 kJ/mole) is comparable to that of weak covalent bonds (155 kJ/mol), and a typical covalent bond is only 20 times stronger than an intermolecular hydrogen bond. These bonds can occur between molecules (intermolecularly), or within different parts of a single molecule (intramolecularly). The hydrogen bond is stronger than a van der Waals interaction, but weaker than covalent, or ionic bonds. This type of bond occurs in both inorganic molecules such as water and organic molecules such as DNA.

Intermolecular hydrogen bonding is responsible for the high boiling point of water (100 °C). This is because of the strong hydrogen bond, as opposed to other group 16 hydrides. Intramolecular hydrogen bonding is partly responsible for the secondary, tertiary, and quaternary structures of proteins and nucleic acids.